<?php
    // +----------------------------------------------------------------------
    // | ThinkPHP [ WE CAN DO IT JUST THINK ]
    // +----------------------------------------------------------------------
    // | Copyright (c) 2006~2015 http://thinkphp.cn All rights reserved.
    // +----------------------------------------------------------------------
    // | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
    // +----------------------------------------------------------------------
    // | Author: yunwuxin <448901948@qq.com>
    // +----------------------------------------------------------------------
    namespace think\process\pipes;
    abstract class Pipes {
        const CHUNK_SIZE = 16384;
        /** @var array */
        public $pipes = [];
        /** @var string */
        protected $inputBuffer = '';
        /** @var resource|null */
        protected $input;
        /** @var bool */
        private $blocked = true;

        /**
         * 返回用于 proc_open 描述符的数组
         * @return array
         */
        abstract public function getDescriptors();

        /**
         * 返回一个数组的索引由其相关的流，以防这些管道使用的临时文件的文件名。
         * @return string[]
         */
        abstract public function getFiles();

        /**
         * 文件句柄和管道中读取数据。
         * @param bool $blocking 是否使用阻塞调用
         * @param bool $close    是否要关闭管道，如果他们已经到达 EOF。
         * @return string[]
         */
        abstract public function readAndWrite($blocking, $close = false);

        /**
         * 返回当前状态如果有打开的文件句柄或管道。
         * @return bool
         */
        abstract public function areOpen();

        /**
         * {@inheritdoc}
         */
        public function close() {
            foreach ($this->pipes as $pipe) {
                fclose($pipe);
            }
            $this->pipes = [];
        }

        /**
         * 检查系统调用已被中断
         * @return bool
         */
        protected function hasSystemCallBeenInterrupted() {
            $lastError = error_get_last();
            return isset($lastError['message']) && false !== stripos($lastError['message'], 'interrupted system call');
        }

        protected function unblock() {
            if (!$this->blocked) {
                return;
            }
            foreach ($this->pipes as $pipe) {
                stream_set_blocking($pipe, 0);
            }
            if (null !== $this->input) {
                stream_set_blocking($this->input, 0);
            }
            $this->blocked = false;
        }
    }
